A known coaxial telecommunications cable is constituted by a central conductor, a dielectric core which is extruded and trued, a metal tube tightly embracing the core and forming the outer conductor and an outer sheath made of a plastics material on the outer conductor. Such a cable is repaired in four operations:
connection of the central conductor; PA1 moulding of the dielectric; PA1 reconstitution of the outer conductor; and PA1 reconstitution of the outer sheath.
The invention relates to the third operation.
Up to now, the aluminium outer conductor has been reconstituted as follows: a metal strip of suitable size is formed round the insulator on a bare portion of outer conductor with a gap of a few millimeters at each end.
Electric continuity is provided by strips wound in a helix overlapping each of the two discontinuities and spot welded at each of their ends firstly to the added metal strip and secondly to the conductor of the cable. The strips are spot welded either cold by crushing and raising the external conductor, or with an electric arc. Such reconstitution gives full satisfaction from the electrical point of view. However, from the mechanical point of view, the method in accordance with the prior art has a number of disadvantages. In particular, spot welding is impossible in the case of outer conductors which are originally glued to the core when they are applied thereto. Indeed, cold welding is not possible because the outer conductor cannot be raised; hot welding is also impossible because the molten metal is polluted by the molten surface of the polyethylene. Further, mechanical resistance to bending is poor. Lastly, in the case of a connection between cables of different sizes, the reconstitution of the outer conductor is not possible, without major preparation, on the diameter-transition portion of insulator.
Preferred application of the present invention remedy these various disadvantages. Indeed, the external conductor can be reconstituted simply while still providing high mechanical resistance to bending.